sencha generate theme creating config.rb with wrong css_path?

When I do the 'compass compile' command it works but the resulting app.css is incorrectly located.
Its ended up in "myapp/resources/sass/css/app.css" rather than "myapp/resources/css/mynewtheme/app.css".

Looking at the config.rb in the theme I created I can see the problem...

Without the change to the config.rb file I just keep picking up the stock extjs theme.
With the adjusted css_path my modifications show up.

I was expecting the generate theme + compass compile + test to work out of the box, i.e. not require tweaking or file moving.
Does this looks like a 'sencha generate theme' bug on the css_path in the config.rb file?